A crash involving a suspected drunk driver closed a freeway ramp in Petaluma for more than two hours early Sunday, the CHP said.

A 1998 Chevrolet Silverado was southbound on Petaluma Boulevard about 1:25 a.m. when it went off the edge of the road at the intersection with the northbound on-ramp to Highway 101, Officer Marcus Hawkins said in a press release.

The Silverado rolled over, knocking down a street lamp in a Caltrans construction staging area and dropping a power line across the on- and off-ramps for the freeway.

Victor Mandujano, 22, of Willits was arrested at the scene and booked into the Sonoma County Jail on suspicion of driving under the influence of alcohol, Hawkins said.

The off-ramp was closed from about 1:45 a.m. to 4 a.m.